90% of web projects that go off-rails have the same common point: a rushed or nonexistent brief. Here's how to write one that protects everyone.
What's a brief for?
- Scope the project: what's included, what isn't
- Compare quotes on equivalent terms
- Align teams: leadership, marketing, tech, agency
- Serve as an implicit contract in case of dispute
The minimum viable structure
1. Context and goals
- Who you are (activity, size, positioning)
- Why you're redoing/creating the site
- Measurable goals at 6-12 months
2. Targets
- Primary persona (decision-maker, buyer, user)
- Secondary personas
- Planned acquisition channels
3. Sitemap and features
- Detailed sitemap (main + sub-pages)
- List of critical features (form, payment, client area…)
- "Nice to have" vs "must have"
4. Content
- Who writes the copy? You or the agency?
- Who provides visuals? Photos, videos, icons?
- Is there existing content to migrate?
5. Design
- Inspiring references (3-5 sites you like, with explanations)
- Existing brand guide (logo, colors, typography) or to be created
- Constraints (WCAG accessibility, corporate identity…)
6. Technical
- CMS preferences (WordPress, Shopify, Next.js, agnostic…)
- Existing or to-be-migrated host
- Business integrations (CRM, ERP, analytics, marketing tools)
7. SEO and performance
- Goals (priority keywords, traffic target)
- Minimum Lighthouse score expected (90+ recommended)
- Multilingual need or not
8. Budget and timeline
- Budget range (essential, even if wide)
- Desired go-live date
- External constraints (trade show, product launch…)
9. Governance
- Main client-side contact
- Validation process (committee, individual, deadlines)
- Meeting cadence
10. Expected deliverables
- Exhaustive list: mockups, developed site, training, tech docs, post-launch support
Mistakes that cost dearly
- "I want something modern and clean." Too vague, every agency will interpret differently.
- Not providing a budget. Agencies will protect themselves, quotes will be oversized.
- Copying a competitor. Show references, but explain precisely what you like.
- Forgetting the content phase. That's often the project bottleneck.
- Ignoring maintenance. A site = 20% creation + 80% life after.
Ideal format
- 10-20 page PDF (no more, no less)
- Diagrams, tables, screenshots
- Editable version (Google Doc or Notion) for exchanges
Conclusion
A good brief = 2 to 4 days of upstream work. Those days save you weeks of tension during the project. If you don't know where to start, a serious agency will help you write it in the pre-project phase.
Need help structuring your brief? We can write it with you.
